During the processing of serial data signals, care must be taken to ensure that, in the interest of unambiguity, any coincidence of the edge of a pulse of the data signal with the edge of a pulse of the sampling signal of the data processing system is prevented. In the event of such coincidences, disturbances are caused by so-called glitches. According to U.S. Pat. No. 4,229,699, therefore, one of, e.g., two sampling signals is selected whose edges do not coincide with the edges of the data signal.
Data processing systems implemented with solidstate integrated circuits require a monolithic integrated circuit for detecting such coincidences which provides a signal that triggers a process for measuring the phase relation between sampling and data signals, or a signal for switching to a suitable sampling signal.